Molds are conventionally used to form a fiber bundle into a unitary mass having a cross-sectional shape corresponding to the shape of the mold. For example, U.S. Pat. No. 3,904,343 to Scott, Jr. discloses a mold for forming a bundle of glass fibers into a hexagonal mass. A conventional hexagonal mold 10 of the type shown in the patent to Scott, Jr. is shown in FIG. 1. The mold 10 includes an angle block 12 having a first hexagonal surface 14 and an angle block 16 having a second hexagonal surface 18. The angle block 16 moves laterally in the channel member 14 responsive to rotation of a jack screw 20. A hexagonal bundle 22 of fibers is placed in that bottom portion of the mold formed by the channel member 14 and angle block 16. Three upper angle blocks 30, 32, 34, each of which has a respective hexagonal surface 36, 38, 40, is then placed on the bundle 22. The upper angle blocks 30, 32, 34 move downwardly to compress the bundle 22 during the molding operation. Also, the angle block 16 may move laterally to compress the bundle 22. It will be apparent that the angle blocks 30, 32, 34 move not only relative to the channel member 12, but also relative to each other. Under these circumstances, the fiber bundle 22 will accurately assume a hexagonal configuration only if the hexagonal symmetry of the angle blocks 30, 32, 34 is maintained while the blocks move relative to each other. However, since there is no mechanism to ensure that symmetry is maintained, the prior art mold 10 may be incapable of forming hexagonal fiber masses with sufficient accuracy.
There is therefore a need for a mold that can accurately form a bundle of fibers into a hexagonal mass without spatial distortion.